Eye Glance Behavior Research Articles

Effects of phone type on driving and eye glance behaviour while text-messaging

This study examined whether phone interface – touch screen keyboard vs. numeric keypad – moderates the impact of sending and receiving text messages on simulated driving performance and eye glance behaviour. The high visual–manual demands of text messaging are known to degrade driving performance and these effects may be exacerbated by the absence of tactile cues when using a touch screen phone. Twenty-four participants (25–50years) sent and received text messages on either a touch screen or numeric keypad phone while driving a simulated freeway environment. As expected, compared to baseline, receiving and particularly sending text messages led to decrements in speed monitoring, decreased the amount of time spent looking at the forward roadway by up to 29%, and increased subjective workload. The performance degradations observed were similar across the numeric keypad and touch screen keyboard phones. Future research should further investigate the possible moderating effects of phone interface type on distraction using longer text message tasks and under more challenging driving conditions.

Relationship between Eye Glance Behavior and Hand Movement on Mouse and Touch-panel Operations

Relationship between Eye Glance Behavior and Hand Movement on Mouse and Touch-panel Operations

Eye Glance and Head Turn Correspondence during Secondary Task Performance in Simulator Driving

Driver eye glance behavior is a useful input to estimate driver visual attention to the road scene. However, eye tracking in an automobile is currently both expensive and prone to various types of degradation. Because head rotation provides a larger target for sensing than eyeball rotation, head pose monitoring may sometimes serve as a surrogate for driver eye glances. To investigate the correspondence between eye gaze and head pose while driving on a simulated rural highway, participants were asked to take 1, 2 or 4 glances to read aloud single capital letters presented on a scrolling LED display placed at various locations: Left Mirror (LM), Left Cluster (LC), Lower Lap (LL), Center Mirror (CM), Center Stack (CS), and Center Console (CC). Manual eye glance and head pose data reduction from video revealed a relatively low likelihood (65% or less) of head turns when reading from the cluster or center mirror. On the other hand, there was a high likelihood (93% or more) of one or more head turns when reading from the lap (e.g., a smartphone held low), left mirror, center console, and center stack locations, regardless of requested number of glances. This study verifies that there may be opportunities for head pose detection and algorithm development to be pursued in future research.

At the cross-roads: An on-road examination of driving errors at intersections

A significant proportion of road trauma occurs at intersections. Understanding the nature of driving errors at intersections therefore has the potential to lead to significant injury reductions. To further understand how the complexity of modern intersections shapes behaviour of these errors are compared to errors made mid-block, and the role of wider systems failures in intersection error causation is investigated in an on-road study. Twenty-five participants drove a pre-determined urban route incorporating 25 intersections. Two in-vehicle observers recorded the errors made while a range of other data was collected, including driver verbal protocols, video, driver eye glance behaviour and vehicle data (e.g., speed, braking and lane position). Participants also completed a post-trial cognitive task analysis interview. Participants were found to make 39 specific error types, with speeding violations the most common. Participants made significantly more errors at intersections compared to mid-block, with misjudgement, action and perceptual/observation errors more commonly observed at intersections. Traffic signal configuration was found to play a key role in intersection error causation, with drivers making more errors at partially signalised compared to fully signalised intersections.

Effect of Using GPS Autosteer Guidance Systems on the Eye-Glance Behavior and Posture of Tractor Operators

Tractor operators are prone to neck and back discomfort and disorders. It is well known that awkward posture is a major contributor to this problem. Previous studies have investigated the prevalence of awkward posture and the resulting discomfort and disorders among tractor operators. They have also suggested various ways to mitigate this problem. With the introduction of new autosteer guidance systems, the tractor operator is relieved from the task of steering the tractor for most of the time during field work. Therefore, it is expected that the operator's posture will change. The goal of this study was to investigate the changes in the eye-glance behavior and posture of tractor operators as a result of using autosteer guidance systems. An eye-tracking system and a camcorder were used to record the eye-glance behavior and posture of 13 tractor operators as they performed seeding operations. The experiment with each operator consisted of two sessions. In one session, the operator used an autosteer system, while in the other session the operator steered the tractor manually. Analysis of the data showed that the eye-glance behavior and posture of the operators were significantly different between the autosteer and manual steering sessions. With the autosteer system, the operators spent less time in an awkward posture, and they changed their posture less frequently. However, even with the autosteer system, the operators spent 1/3 of their time in an awkward posture. Subjective feedback from the operators indicated that more than half of them experienced back or neck/shoulder discomfort during or after seeding. It is essential that the recommendations of the previous studies, such as using large rear-view mirrors or a rotating tractor seat, be evaluated when the operator is using an autosteer system. Other tools, such as video cameras that show the attached equipment, should also be tested to evaluate their effectiveness in reducing the operator's exposure to awkward postures.

The effects of using a portable music player on simulated driving performance and task-sharing strategies

This study examined the effects of performing scrollable music selection tasks using a portable music player (iPod Touch™) on simulated driving performance and task-sharing strategies, as evidenced through eye glance behaviour and secondary task performance. A total of 37 drivers (18–48 yrs) completed the PC-based MUARC Driver Distraction Test (DDT) while performing music selection tasks on an iPod Touch. Drivers’ eye glance behaviour was examined using faceLAB eye tracking equipment. Results revealed that performing music search tasks while driving increased the amount of time that drivers spent with their eyes off the roadway and decreased their ability to maintain a constant lane position and time headway from a lead vehicle. There was also evidence, however, that drivers attempted to regulate their behaviour when distracted by decreasing their speed and taking a large number of short glances towards the device. Overall, results suggest that performing music search tasks while driving is problematic and steps to prohibit this activity should be taken.

Mental Workload Associated with Operating an Agricultural Sprayer: An Empirical Approach

Agricultural spraying involves two major tasks: guiding a sprayer in response to a GPS navigation device, and simultaneous monitoring of rear-attached booms under various illumination and terrain difficulty levels. The aim of the present study was to investigate the effect of illumination, task difficulty, and task level on the mental workload of an individual operating an agricultural sprayer in response to a commercial GPS lightbar, and to explore the sensitivity of the NASA-TLX and SSWAT subjective rating scales in discriminating the subjective experienced workload under various task, illumination, and difficulty levels. Mental workload was measured using performance measures (lateral root mean square error and reaction time), physiological measures (0.1 Hz power of HRV, latency of the P300 component of event-related potential, and eye-glance behavior), and two subjective rating scales (NASA-TLX and SSWAT). Sixteen male university students participated in this experiment, and a fixed-base high-fidelity agricultural tractor simulator was used to create a simulated spraying task. All performance measures, the P300 latency, and subjective rating scales showed a common trend that mental workload increased with the change in illumination from day to night, with task difficulty from low to high, and with task type from single to dual. The 0.1 Hz power of HRV contradicted the performance measures. Eye-glance data showed that under night illumination, participants spent more time looking at the lightbar for guidance information. A similar trend was observed with the change in task type from single to dual. Both subjective rating scales showed a common trend of increasing mental workload with the change in illumination, difficulty, and task levels. However, the SSWAT scale was more sensitive than the NASA-TLX scale. With the change in illumination, difficulty, and task levels, participants spent more mental resources to meet the increased task demand; hence, the illumination, task difficulty, and task level affected the mental workload of an agricultural sprayer operator operating a sprayer in response to a GPS lightbar.

A complete task analysis to measure the workload associated with operating an agricultural sprayer equipped with a navigation device

The objective of this study was to perform a complete task analysis to measure the workload associated with operating an agricultural sprayer equipped with a navigation device. The task analysis included a written questionnaire and subsequent observation of sprayer operators. The questionnaire revealed that the lightbar was the most important source of guidance information (as opposed to relying on guidance information from external field cues). Observation consisted of recording eye-glance behaviour and heart rate variability while operators were spraying in a field setting. The eye-glance data suggest that external cues are more important than the lightbar for providing the necessary navigation information. Thus, the questionnaire and observation data contradict each other. Based on heart rate variability, operators who used a lightbar navigation device experienced more mental workload than operators who used an auto-steer navigation device.

Differences in Off-Road Glances: Effects on Young Drivers’ Performance

Young drivers display more risk-taking behavior than other age groups. Performing distracting tasks is one such risky behavior that is observed among young drivers. However, due to inexperience, young drivers may not be able to appropriately compensate for the effects of distractions. A driving simulator study with 53 young drivers (aged 18–21) was conducted to assess the level of engagement with an in-vehicle secondary task. A cluster analysis revealed three groups of drivers that differed based on eye glance behavior and driving performance: drivers with low-risk, moderate-risk, and high-risk behavior. A subset of these drivers was provided with feedback to help modulate their distracting activities with the riskiest group benefitting most from feedback as indicated by enhanced glance behavior and driving performance. The findings have implications for developing better crash countermeasures to mitigate the effects of distraction.

Evaluation of Mental Workload Associated with Operating an Agricultural Sprayer in Response to Three Different GPS Navigation Aids

In modern agricultural spraying, the commonly used guidance aid includes a GPS lightbar and/or a GPS mapping unit. A lightbar display and a mapping display both present guidance information, but in different formats. A stacked display was developed with the intent of drawing on the advantages of both types of displays. The objective of this research was to identify the display that would produce the least amount of mental workload. Mental workload was measured by performance measures, physiological measures, and subjective rating scales. Performance measures included lateral root mean square error for driving performance and reaction time for secondary task performance. Physiological measures included two measures of eye-glance behavior. The subjective rating scale included the simplified SWAT scales. Sixteen male university students participated in this study. They were trained to drive an agricultural driving simulator. Performance measures clearly indicated that the driving performance and monitoring performance were highest for the lightbar display. Physiological measures also showed a similar trend: less mental workload was associated with the lightbar display. Eye-glance behavior revealed that when the guidance information was available through the stacked and mapping displays, subjects spent more time looking at the display. Subjective rating scales contradicted performance and physiological data; more mental workload was observed for the lightbar display. While performance and physiological measures suggest that the lightbar display induced the lowest mental workload, subjective ratings of workload contradicted these findings.

Eyeglance Behavior of Novice Teen and Experienced Adult Drivers

Eyeglance behavior and scanning patterns may be learned as a driver gains experience and lead to greater situation awareness on the part of the driver. This may help to explain differences observed in the safety records of novice teen and experienced adult drivers. For example, new drivers may focus almost exclusively on the road ahead and spend little time scanning the vehicle's mirrors. However, a novice driver performing a secondary task may spend more time with his or her eyes on the task than on the road, because of unfamiliarity with the vehicle or inexperience with consequences of long glances away from the forward view. For this study, 18 novice teen (under 17.5 years old and within 4 weeks of licensure) and 18 experienced adult drivers performed a set of in-vehicle tasks on a test track. A baseline driving segment was also included. Measures consisted of percentage of eyes-off-road (EOR) time, number of glances, and mean single-glance time. Results showed that teens glanced at the rearview mirror...

Eyeglance Behavior of Novice Teen and Experienced Adult Drivers

Eyeglance behavior and scanning patterns may be learned as a driver gains experience and lead to greater situation awareness on the part of the driver. This may help to explain differences observed in the safety records of novice teen and experienced adult drivers. For example, new drivers may focus almost exclusively on the road ahead and spend little time scanning the vehicle's mirrors. However, a novice driver performing a secondary task may spend more time with his or her eyes on the task than on the road, because of unfamiliarity with the vehicle or inexperience with consequences of long glances away from the forward view. For this study, 18 novice teen (under 17.5 years old and within 4 weeks of licensure) and 18 experienced adult drivers performed a set of in-vehicle tasks on a test track. A baseline driving segment was also included. Measures consisted of percentage of eyes-off-road (EOR) time, number of glances, and mean single-glance time. Results showed that teens glanced at the rearview mirror significantly fewer times than did adults, both during baseline driving and while performing in-vehicle tasks. Teens also had a significantly higher percentage of EOR time than adults had while performing a challenging reading task. The novice teen drivers spent more of their overall EOR time looking at the task display (e.g., cell phone), whereas adults used some EOR time to check mirrors or windows. Overall findings indicate that novice teens may lack the situation awareness of experienced adults.

Eye Glance Behavior of Van and Passenger Car Drivers During Lane Change Decision Phase

Data are presented on the eye glance behavior of passenger car and van drivers before the start of discretionary lane changes. Thirty-nine volunteers ranging from 20 to 60 years of age served as either van drivers (N = 19) or passenger car drivers (N = 20) in the study. Each driver used an instrumented vehicle and was accompanied by a ride-along observer in daylight and dry pavement conditions. The test route included driving on both public highways at 55 mph or more and city roads at 25 to 35 mph. A total of 549 lane changes (290 for vans, 259 for passenger cars) were analyzed in terms of driver eye glance behavior 10 s before the lane change start. Results indicated that for left-to-right lane changes, the probability of a glance to the center mirror was substantially higher than the probability of a glance to the right side mirror. For right-to-left lane changes, the probability of a glance to the center mirror was substantially less than that for rightward lane changes, and the probability of a glance to the left side mirror was appreciably higher than that for right side mirror use in rightward lane changes. These results held for both van and passenger car drivers. Except for a slightly higher probability of over-the-shoulder glances on city roads, these results hold for both highway and city street driving. These data should be factored into the design of lane change warning system displays and mirror systems.

Eye Glance Behavior of van and Passenger Car Drivers during Lane Change Decision Phase

Data are presented on the eye glance behavior of passenger car and van drivers before the start of discretionary lane changes. Thirty-nine volunteers ranging from 20 to 60 years of age served as either van drivers (N = 19) or passenger car drivers (N = 20) in the study. Each driver used an instrumented vehicle and was accompanied by a ride-along observer in daylight and dry pavement conditions. The test route included driving on both public highways at 55 mph or more and city roads at 25 to 35 mph. A total of 549 lane changes (290 for vans, 259 for passenger cars) were analyzed in terms of driver eye glance behavior 10 s before the lane change start. Results indicated that for left-to-right lane changes, the probability of a glance to the center mirror was substantially higher than the probability of a glance to the right side mirror. For right-to-left lane changes, the probability of a glance to the center mirror was substantially less than that for rightward lane changes, and the probability of a glance to the left side mirror was appreciably higher than that for right side mirror use in rightward lane changes. These results held for both van and passenger car drivers. Except for a slightly higher probability of over-the-shoulder glances on city roads, these results hold for both highway and city street driving. These data should be factored into the design of lane change warning system displays and mirror systems.

Eye Glance Behavior During Lane Changes and Straight-Ahead Driving

Understanding drivers' eye behavior before lane changing is an important aspect of designing usable, safe lane-change collision-avoidance systems (LCAS) that will fit well with drivers' expectations. This understanding could lead to improvements for LCAS as well as for a variety of other collision avoidance systems. Findings regarding driver eye glance behaviors are presented in a comparison of lane change maneuvers with straightahead (baseline) driving events. Specific eye glance patterns before lane change initiation were observed. When preparing to make a lane change to the left as compared with driving straight ahead, drivers doubled the number of glances toward the rearview mirror and were much more likely to look at other locations associated with moving to the left, including the left mirror and blind spot. On the basis of the eye glance patterns observed and previous results, the following recommendations are made: (a) visual presence detection indicator displays should be used to provide informat...

Eye Glance Behavior during Lane Changes and Straight-Ahead Driving

Understanding drivers’ eye behavior before lane changing is an important aspect of designing usable, safe lane-change collision-avoidance systems (LCAS) that will fit well with drivers’ expectations. This understanding could lead to improvements for LCAS as well as for a variety of other collision avoidance systems. Findings regarding driver eye glance behaviors are presented in a comparison of lane change maneuvers with straight-ahead (baseline) driving events. Specific eye glance patterns before lane change initiation were observed. When preparing to make a lane change to the left as compared with driving straight ahead, drivers doubled the number of glances toward the rearview mirror and were much more likely to look at other locations associated with moving to the left, including the left mirror and blind spot. On the basis of the eye glance patterns observed and previous results, the following recommendations are made: ( a) visual presence detection indicator displays should be used to provide information about vehicles in the rear adjacent lane any time a vehicle is detected, ( b) a presence indicator should be presented in a visual format, and ( c) the left mirror and rearview mirror locations should be considered for providing lane change information to the driver. The process of acquiring and analyzing eye glance movements is well worth the investment in resources. However, prototype systems must be tested before implementation, and the exact location and format of warning systems warrant a separate research and development effort to ensure safety and reliability.

Methodology for Capturing Driver Eye Glance Behavior during In-Vehicle Secondary Tasks

Driving is a visual task; any driver behavior that takes the driver's visual attention from the driving environment is likely to increase the risk of a crash. Many new intelligent transportation systems telematics applications are now being installed in cars, and some of these may result in substantial degradation of visual attention. Accurately capturing driver eye glance behavior during the evaluation of these devices is critical to assessing the safety impact of engaging in secondary tasks while driving. The development of a methodology is reported; it reliably determines on-road and off-road eye glance duration by using video data collected during highway driving evaluation trials while drivers were engaged with secondary tasks. Human raters determined glance location and duration by detailed coding of the driver's eye movements on the videos. The raters agreed most of the time, but sufficient disagreement suggested that using the consensus of multiple raters significantly improved the reliability of the resulting eye glance data.

Methodology for Capturing Driver Eye Glance Behavior During In-Vehicle Secondary Tasks

Driving is a visual task; any driver behavior that takes the driver's visual attention from the driving environment is likely to increase the risk of a crash. Many new intelligent transportation systems telematics applications are now being installed in cars, and some of these may result in substantial degradation of visual attention. Accurately capturing driver eye glance behavior during the evaluation of these devices is critical to assessing the safety impact of engaging in secondary tasks while driving. The development of a methodology is reported; it reliably determines on-road and off-road eye glance duration by using video data collected during highway driving evaluation trials while drivers were engaged with secondary tasks. Human raters determined glance location and duration by detailed coding of the driver's eye movements on the videos. The raters agreed most of the time, but sufficient disagreement suggested that using the consensus of multiple raters significantly improved the reliability of ...

Hand-Held or Hands-Free? The Effects of Wireless Phone Interface Type on Phone Task Performance and Driver Preference

The number of wireless phone subscribers in the U.S. is constantly growing. Studies have shown that use of wireless phones while driving contributes to crashes. Efforts to pass legislation allowing only hands-free wireless phone use while driving are widespread and based on the assumption that a hands-free interface is safer than a hand-held one. The National Highway Traffic Safety Administration conducted a driving simulator study to examine the effects of phone interface type on driving performance and drivers' ability to perform phone tasks. Participants' phone interface preferences were also recorded. Fifty-four participants drove a simulated freeway route with each of three phone interfaces: hand-held, headset hands-free (voice dialing and headset), and voice dialing hands-free (voice dialing with cradle-mounted speaker phone). Although post-drive questionnaire results show that participants rated the hand-held interface to be most difficult to use, this interface was associated with the fewest dialing errors and significantly faster dialing times than the two hands-free interfaces. Drivers answered the phone more quickly when using the voice dialing hands-free phone interface than when using the hand-held or headset hands-free interfaces. Younger drivers answered the phone significantly more quickly than the older drivers. Hang up times were significantly faster in the voice dialing hands-free condition and were slowest in the headset hands-free condition. Conversation task performance did not differ as a function of phone interface. Thus, although drivers considered them easier to use than hand-held phone interfaces, hands-free interfaces were more time-consuming to interact with while driving. Further analyses of these data will investigate how other aspects of phone task performance are related to eye glance behavior and driving performance.

Commentary on "Car Drivers' Adjustments to Cyclists at Roundabouts"

This paper presents a commentary on an earlier paper in this journal entitled Car drivers' adjustments to cyclists at roundabouts. The author of this commentary believes that the original paper provides important clues to vehicle--cyclist collision analysis. The author posits that it would also be beneficial to take into account the eye glance behavior of the cyclists themselves. Combining this study with an analysis of driver behavior when exiting roundabouts would provide a comprehensive and useful extension of this topic. Other suggestions are also made that the author believes would enhance the original research setting.